Field of the Invention
The present invention relates to a measuring system.
Description of the Background Art
WO 2010/060607 A2, which corresponds to U.S. Pat. No. 8,680,847, discloses an IC package with a semiconductor chip with an integrated circuit and an integrated magnetic sensor. A permanent magnet, whose magnetic flux penetrates the sensor, is spaced apart from the semiconductor chip package. If an object to be measured approaches the head end of the semiconductor chip, the magnetic flux density through the sensor changes.
U.S. Pat. No. 7,250,760 B2 discloses integrated magnetic Hall sensors in which a permanent magnet is disposed in the IC package. In this case, the Hall sensors are arranged in such a way to the field of the permanent magnet that a Hall voltage is generated without an external field effect.
DE 698 27 559 T2, which corresponds to U.S. Pat. Nos. 5,963,028 and 6,265,865, discloses a package for a magnetic field sensor. Typically, an air gap is defined as the distance between an exciter and the outer surface of the package, which contains a sensing element of the magnetic field sensor. An “effective air gap” can be described as the distance between the exciter and the sensing element itself. Magnetic field sensors typically contain a permanent magnet and a sensing element, which is encapsulated in a package. This package type, however, is not suitable for harsh environments, particularly those in an automobile. Therefore, sensing elements packaged in such a way are enclosed further in an additional package (overmold), which provides protection from moisture and dirt. This results in a decrease in the peak magnetic field strength, as a tooth passes through the magnetic field in proximity to the sensor element. It is desirable in DE 698 27 559 T2 to have the sensor element as close as possible to the magnet, because the magnetic field decreases as a function of the air gap. A smaller distance allows the use of a small magnet with a lower energy product.
DE 10 2012 203 001 A1, which corresponds to U.S. 2012/0217960, discloses a 3-D magnetic sensor. The magnetic field sensor has a flat soft-magnetic body, which is arranged on a surface of a substrate, which has a magnetic sensor array having a plurality of spatially diverse magnetic sensor elements, disposed in a predetermined configuration. In the presence of an external magnetic field, the flat soft-magnetic body is magnetized to generate a reactionary magnetic field. The plurality of magnetic sensor elements are each configured to measure a magnetic field value of a superposition of the external magnetic field and of the reactionary magnetic field along a first axis (e.g., a z-axis), which results in a plurality of spatially diverse measurements of the magnetic field component along the first axis. The plurality of spatially diverse measurements can be used to compute magnetic field components of the external magnetic field along a plurality of axes (e.g., x-axis, y-axis, and z-axis).